﻿using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace 练习
{
    class Program
    {
        static void Main(string[] args)
        {
            Console.Write("请输入一个数：");
            int a = Convert.ToInt32(Console.ReadLine());
            for (int i = 1; i <= a; i++)
            {
                for (int j = 1; j <= a - i; j++)
                {
                    Console.Write("·");
                }
                for (int t = 1; t <= 2 * i - 1; t++)
                {
                    Console.Write("●");
                }
                Console.Write("\n");
            } //菱形上半部分
            for (int p = 1; p < a; p++) //菱形下半部分
            {
                for (int q = 1; q <= p; q++)
                {
                    Console.Write("·");
                }
                for (int k = 1; k < 2 * (a - p); k++)
                {
                    Console.Write("●");
                }
                Console.Write("\n");
            }

            Console.ReadKey();

        }
    }
    }

